Catalogue of the Parisian electrical instrument maker J Carpentier, c1920, successor to Ruhmkorff.
The Catalogue appears to have been compiled by amassing several different, independently-paginated, 'fascicules' under a single cover, according to the needs of the client. Different clients would have received different compilations.
The telephone number 'Saxe 05-65' dates the Catalogue to between 1912, when this form of number was adopted, and 1923, when the Saxe exchange was renamed Ségur. The pink label 'Majoration 150%' suggests a date after the inflationary effects of World War I had begun (inflation 1912-1919 = 153%, 1912-1923=227%, but electrical instruments may not have followed general inflation).